PHP operators

Introduction

PHP is a widely used programming language for building dynamic web applications. One of the fundamental aspects of PHP programming is the use of operators. Operators are symbols or keywords that perform specific operations on variables and values.

In PHP, operators are used to perform arithmetic, comparison, assignment, logical, and bitwise operations. Understanding how to use operators in PHP is crucial for writing efficient and effective code. This knowledge helps developers manipulate data and control program flow, allowing them to create complex web applications with ease.

PHP Arithmetic Operators

In PHP, Arithmetic operators are used to perform mathematical operations on numeric values. These operators include addition (+), subtraction (-), multiplication (*), division (/), and modulus (%). The modulus operator returns the remainder of a division operation. Let's explore these operators in more detail with the help of examples:

1. Addition (+): The addition operator is used to add two or more numeric values together. For example:

2. Subtraction (-): The subtraction operator is used to subtract one numeric value from another. For example:

3. Multiplication (*): The multiplication operator is used to multiply two or more numeric values together. For example:

4. Division (/): The division operator is used to divide one numeric value by another. For example:

5. Modulus (%): The modulus operator is used to return the remainder of a division operation. For example:

PHP Assignment Operators

In PHP, Assignment operators are used to assign values to variables. These operators are shorthand versions of common assignments, such as addition or subtraction, and can make code more concise and readable.

1. Addition assignment (+=): The addition assignment operator is used to add a value to a variable and assign the result to the same variable. For example:

Output

2. Subtraction assignment (-=): The subtraction assignment operator is used to subtract a value from a variable and assign the result to the same variable. For example:

Output

3. Multiplication assignment (*=): The multiplication assignment operator is used to multiply a variable by a value and assign the result to the same variable. For example:

Output

4. Division assignment (/=): The division assignment operator is used to divide a variable by a value and assign the result to the same variable. For example:

Output

Now let us read about PHP Comparison Operators:

PHP Comparison Operators

In PHP, Comparison operators are used to comparing two values and return a Boolean (true or false) value based on the comparison result.

1. Equal (==): The equal operator checks if two values are equal or not. For example:

Output

2. Identical (===): The identical operator checks if two values are identical or not, including their data types. For example:

Output

3. Not equal (!=): The not equal operator checks if two values are not equal or not. For example:

Output

4. Not identical (!==): The not identical operator checks if two values are not identical or not, including their data types. For example:

Output

5. Greater than (>): The greater than operator checks if the first value is greater than the second value or not. For example:

Output

6. Less than (<): The less than operator checks if the first value is less than the second value or not. For example:

Output

In this example, the "less than" operator compares $number1 and$number2 and returns true because the first value is less than the second one. Run all the code snippets in your editor for a better and clear explanation.

PHP Increment / Decrement Operators

Pre-increment operator increases the value of a variable by one and then returns the new value. On the other hand, the post-increment operator returns the current value of the variable and then increases the value by one.

Similarly, the pre-decrement operator decreases the value of a variable by one and then returns the new value. The Post-decrement operator returns the current value of the variable and then decreases the value by one.

Output

In the above code, we have a variable $x with a value of 5. We have used all the operations like pre-increment, post-increment, pre-decrement, and post-decrement operators on this variable.

PHP Logical Operators

PHP provides various logical operators that are used to combine and manipulate boolean expressions. The three main logical operators in PHP are AND, OR, and NOT.

1. AND Operator

The AND operator returns true if both operands are true. It is represented by the symbol && or and in PHP. Let us see an example :

Output

Both x and y are positive numbers.

2. OR Operator

The OR operator returns true if at least one of the operands is true. It is represented by the symbol || or or in PHP. Let us see an example :

Output At least one of x and y is positive.

3. NOT Operator

The NOT operator is used to negate the value of a boolean expression. It is represented by the symbol ! in PHP. Let us see an example :

Output

x is positive.

4. Logical operators can be combined to form more complex boolean expressions, and parentheses can be used to control the order of evaluation. Let us see an example :

Output One operand is positive and one is negative.

PHP string Operators

PHP provides several operators that can be used to manipulate strings. These operators include concatenation, assignment, and comparison operators.

String Concatenation Operator

The concatenation operator is used to join two or more strings together. It is represented by a dot (.) in PHP. Let us see an example:

Output

In the above example, the dot operator is used to concatenate the $name and$age variables with the "Hello, my name is" and "years old" strings.

String Assignment Operator

The assignment operator can be used to assign a string value to a variable. It is represented by the = sign in PHP. Let us see an example:

Output

In the above code, the $name variable is assigned the value "John" using the assignment operator.

String Comparison Operators

PHP provides several operators that can be used to compare two strings. These operators include ==, ===, !=, !==, <, >, <=, and >=. Let us see an example:

**Output **

The names are different.

In the above example, the == operator is used to compare the $name1 and$name2 variables. Since the strings are not equal, the else block is executed and the message "The names are different" is printed.

PHP Array Operators

PHP provides several operators that can be used to manipulate arrays. These operators include union, equality, identity, inequality, and non-identity operators.

1. Union Operator

The union operator is used to merge two or more arrays together. It is represented by the + operator in PHP. Let us see an example:

Output

In the above example, the + operator is used to merge the $array1 and$array2 arrays into a single array called $mergedArray.

2. Equality Operator

The equality operator is used to check if two arrays have the same values, ignoring their keys. It is represented by the == operator in PHP.

Output

In the above example, the == operator is used to check if the $array1 and$array2 arrays have the same values, even though their order is different.

3. Identity Operator

The identity operator is used to check if two arrays are identical, including their keys and values. It is represented by the === operator in PHP.

Output

PHP conditional operators

PHP conditional assignment operators are a shorthand way to assign values to variables based on a certain condition. There are two types of conditional assignment operators in PHP: the ternary operator and the null coalescing operator.

1. Ternary Operator

The ternary operator is used to assign a value to a variable based on a condition. It is represented by the ? operator in PHP.

Output

In the above example, the ternary operator is used to check if the $age variable is greater than or equal to 18. If it is, the$isAdult variable is assigned the value "Yes". If it is not, the $isAdult variable is assigned the value "No".

2. Null Coalescing Operator

The null coalescing operator is used to assign a default value to a variable if it is null or undefined. It is represented by the ?? operator in PHP.

Output

In the above example, the null coalescing operator is used to check if the $name variable is null or undefined. If it is, the$currentName variable is assigned the value of $defaultName, which is "Yash". If$name has a value other than null or undefined, the $currentName variable is assigned that value instead.

Precedence of PHP Operators

Precedence of PHP operators determines the order in which the different operators are evaluated in an expression. Operators with higher precedence are evaluated before operators with lower precedence. Here are some examples of operator precedence in PHP:

1. Arithmetic Operators

Arithmetic operators have higher precedence than assignment operators. For example:

In the above example, as we that the multiplication operator has higher precedence than the addition operator. So, the expression 2 * 3 is evaluated first, and then the result is added to 10.

2. Comparison Operators

Comparison operators have lower precedence than arithmetic operators.

In the above example, the addition operator is evaluated first, and then the comparison operator is evaluated. So, the expression 10 + 2 is evaluated to 12, and then it is compared to 5.

3. Logical Operators

Logical operators have lower precedence than comparison operators.

In the above example, the comparison operators are evaluated first, and then the logical operator is evaluated. So, the expression 10 > 5 is evaluated as true, and then it is AND with the expression 5 < 3, which is evaluated as false.

MCQ's

a. What is the difference between the "==" and "===" operators in PHP?

i) Both operators check for equality of values and data types
ii) The "==" operator checks for equality of values, but not data types
iii) The "===" operator checks for equality of data types, but not values
iv) The "===" operator checks for equality of both values and data types
v) Correct Answer: iv) 

b. What is the use of the "++" operator in PHP?

i) It subtracts 1 from a variable's value
ii) It adds 1 to a variable's value
iii) It multiplies a variable's value by 2
iv) It divides a variable's value by 2
v) Correct Answer: ii) 

c. Which operator is used to concatenate two strings in PHP?

i) "+"
ii) "-"
iii) "*"
iv) "."
v)Correct Answer:iv) .